| Autor: |
Vladyslav Seminko, Pavel Maksimchuk, Iryna Bespalova, Yuri Malyukin |
| Jazyk: |
angličtina |
| Rok vydání: |
2019 |
| Předmět: |
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| Zdroj: |
Crystals, Vol 9, Iss 2, p 114 (2019) |
| Druh dokumentu: |
article |
| ISSN: |
2073-4352 |
| DOI: |
10.3390/cryst9020114 |
| Popis: |
Luminescence properties of Lu2SiO5:Ce3+ and Y2SiO5:Ce3+ nanocrystals were studied using photo- and X-ray luminescence techniques. The crystal structure of Re2SiO5 nanocrystals (P21/c space group) differs from the crystal structure of Re2SiO5 bulk crystals (C2/c space group) with 9- and 7-oxygen-coordinated cation positions instead of 6- and 7-coordinated ones observed for Re2SiO5 bulk crystals. Two optical centers (Ce1 and Ce2) were observed for Re2SiO5:Ce3+ nanocrystals originating from cerium ions substituting 9- and 7-oxygen-coordinated cation sites. Preferential substitution of larger cation sites by cerium ions leads to higher photoluminescence intensity of Ce1 centers, however, Ce2 centers are the main centers for electron-hole recombination, so only Ce2 band is observed in X-ray luminescence spectra. The features of oxygen coordination of Ce1 and Ce2 centers and high content of oxygen vacancies in Re2SiO5:Ce3+ nanocrystals can provide preferential trapping of electrons near Ce2 centers, and therefore, the dominant role of Ce2 band in X-ray luminescence spectra. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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